This invention relates to outsoles for footwear and in particular to those disclosed by Whatley, U.S. Pat. No. 5,005,299, which is hereby incorporated by reference herein.
Stubblefield, U.S. Pat. Nos. 4,372,058, 4,546,556, 4,550,510, 4,741,114, and 4,449,307 describes an outsole for an athletic shoe. The outsole is provided with several outwardly disposed flexible lugs inclined at an obtuse angle to the lower surface of the shoe sole. This angular configuration allows the lugs to spread outwardly upon impact with the ground and thereby dissipate impact forces away from the foot and leg of the wearer. A series of lugs is formed around the periphery of the shoe sole to define a central concavity in which further lugs may be located. These further lugs have a lesser vertical dimension than the outermost lugs. In order to prevent the outermost lugs from being broken, a reinforcing means may be provided as a web extending between adjacent lugs. This web extends around the periphery of the outsole to connect adjacent lugs. It does not extend within the central concavity. The shoe sole also may be provided with a shock absorbing inner portion (distinct from the outsole) in which a plurality of parallel transverse walls extend vertically upward.
Martin et al., U.S. Pat. No. Des. 89,204 describes a shoe sole including a central cavity in the midfoot which has inwardly sloped inside walls. Carrier, U.S. Pat. No. 1,988,784 describes a sport shoe sole including cavities with inwardly sloped inside walls. Maselter, U.S. Pat. No. 2,279,891 describes a shoe heel including circular ribs with vertical walls and transverse webs. Hogg, U.S. Pat. No. 2,424,463 describes a shoe sole which includes circular suction cups defining cavities with inwardly sloped inside walls of curved cross section. Johns, U.S. Pat. No. Des. 201,952, shows a shoe sole including linear cavities with inwardly sloped inside walls of curved cross section. Cameron, U.S. Pat. No. 3,739,497 describes a shoe sole with a metal heel cleat which includes a cavity with inwardly sloped inside walls. Tanel, U.S. Pat. No. 4,577,422 describes the sole of a shoe with a circular forefoot cleat enclosing a cavity with inwardly sloped walls. Norton et al., U.S. Pat. No. 4,730,402, Ganter et al., U.S. Pat. No. 4,697,361, Polus WO 89/11047, Halberstat, U.S. Pat. No. 4,259,792, Reiner et al., U.S. Pat. No. 4,094,081, Lombard et al., U.S. Pat. No. 3,100,354, Anderie, U.S. Pat. No. 4,281,467, Masera, U.S. Pat. No. 2,887,794, Danieli, U.S. Pat. No. 4,680,875, Chrencik, U.S. Pat. No. 2,885,797, Bowerman, U.S. Pat. No. 3,793,750, Dassler, U.S. Pat. Nos. 3,808,713 and 3,818,617, Hollister et al., U.S. Pat. No. 4,043,058, Riggs, U.S. Pat. No. 4,085,527, Saurwein, U.S. Pat. No. 4,096,649, Bowerman, U.S. Pat. No. 4,128,950, Schmohl, U.S. Pat. No. 4,266,349, Rudy, U.S. Pat. No. 4,271,606, and Stirtz et al., U.S. Pat. No. 4,297,796, describe various shoe and sole designs.